Camera shutter



C. C. FUERST CAMERA SHUTTER Feb. 27, 1945.

Original Filed 'May -4, i945 Rm. s .0 FW n C A L R m M Y B Reissued Feb. 27, 1945 man Kodak Company, Rochester, poraflon of New Jersey N. Y., a cor- Orlginal No. 2,356,455, dated August 22, 1944, Se-

rial No. 485,597, May 4, 1943. Application tor reissneNovember 10, 1944, Serial No. 562,836

. 7 Claims. This invention relates to photography and more particularly to simple and inexpensive shutters for photographic cameras. One object of my invention is to provide a shutter consisting of a minimum imnnher of parts which can be readily assembled and which is designed primarily to give a. single reliable exposure. Another object of my invention is to provide asimple type of shutter in which a simple type or drive is used to actuate the shutter blades. Other obiectswill appear from the .folhwing specification, the novel features being particularly pointed out in the claims at the end thereot.

In the drawing wherein like reference characters denote iike'parteihrouzlmut:

Fig. .1 is a top plan view of a s'hntterconstmcted in accordance with apreferred embodiment of Fig. 4 is a view similar to 3 but with the shutter parts being tensioned to produce an exposure; and

- .Ffig. 5 is a fragmentary line '55 of Fig. .1.

My invention consists in providing an inexpensive type of two-blade shutter in which the blades are moved .in opposite directions to open and close an exposure aperture. This movement takes place when a shutter trigger is depressed to set and release .a master member which contacts directly with the shutter leaves. By construction, which will be hereinafter fully described, it is possible to produce reliable exposures with a shutterco'nstructed with a minimum number of parts and with a shutter structure which is extremely simple toboth make and assemble.

More specifleally,my shutterma'y consist of a support 1 which may be in the form of a shutter detail section taken on casing having'a bottom walltwith a central exposure aperture "3 and an upstanding flange 1! extending around the periphery of the shutter.

W n spaced pivots I which lie to one side of the exposure aperture 3. The shutter leaves are similarin shape, one being the right-handed and the other being the left-handed. One of the shutter leaves i carries an upstanding shutter leaf 'operating pin '9 which, as best shown in Fig. 5., E

tends through a slot ID in the opposite shutter leaf 1. The pin flexte'nds upwardly through a slot ID in the mechanism plate 5 and, by oscillating this pin in a general radial direction with respect to the exposure aperture 3, the shutter leaves may be moved to open and close the expo* sure aperture "3.

.The master member H is pivoted at 1'2 to the I mechanism plate and a spring [3 encircling this pivot always tends to drive the master member 11 in. a counter clockwise direction as indicated the arrow in l. A lug i4 strucku-p from the mechanism plate 5 provides a nest position against which the master member usually lies as indicated in Fig. 1. end 15 of the master member is formed outwardly and downwardly into a flange I16 which, as best shown in Fig. 5, is" provided with a cam surface .Il on the extreme end, with a cutout l8 through the central sectionand with a beveledsuriace 18 on the portion posite the cam end H. It should be nodded that the cam end 11 has a portion!!! which may engage an edge of the master member 1.] sothatthe cam I1 is prevented from moving .amaterial distance toward the exposure aperture; even though the flange I6 is sufiiciently resilient to move inn:

opposite direction :a distance sufilcient to permitthe pin 8 to pass therebetween as indicated in Fig. 4. v p

The master member is set and released by means at .a. triggerii ,pivotally attached at 22 to the mechanism plate and normally moved in [a clockwise direction by means of a spring 23. of rest or the trigger is shown in Fig. L

With the parts in this position a downward movement on the trigger .21 will cause a blade ring operating arm .24 extending. inward-1y from the trigger to engage the flange portion 19o: the master member ii and as trigger moves downwardly the spring cam element ll will move outwardly, as shown ih Fig. 4,-to permit the ,pin 9 to pass, after which the spring ca'in l1 springs inwardly, so that, when. the trigger reaches the position slightly beyond that shown in Fig. ,2 and 1 thearm 24' releases or rides of! the master memberflange "I95, the spring 1*! may rapidly move the master member ina counter-clockwise direction about its pivot l2 causing the cam to first strike the pin 9 as shown in ,Fig. '2. Continued movement of the master member causes the pin exerts a thrust on the pin 9 and toward the cen-' ter of the exposure aperture 3.

After an exposure has been thus made the trigger spring 23 returns the trigger 2| to itsFig. 1 position. During this movement the beveled surface 28 of the trigger engages and rides under 1. A camera shutter comprising, in combination, an apertured support, a pair of shutter blades pivotally mounted thereon on spaced pivots, one blade carrying a pin projecting through a slot in the other blade, a master member pivotally carried by the support and spring held in a rest position, a spring. flange carried by the master member including a cam shaped end and having a cut out therein, said master member pivot being so located relative to the blade pin that movement on said pivot may engage the the beveled flange l9 of the master member until i it engages the end of the cut-out portion I8 as shown in Fig. 5. From this position another ex-. posure can be'made by repeating the operations above described which occurs when the trigger 2| is depressed.

There are a number of advantages in 'my improved construction. One of these advantages is that the construction of the spring cam, which ma be fo'rmed directly from the material of which. the master member II is made, is such that fine adjustments need not be made. In initially laying out the shutter it is a simple matter to provide a cam shape which will hold the shutter blades open the required length of time. This can be done by making that portion H of the oam longer or shorter as may be required.

liavingonce established the length of this portion of the cam, no further adjustments need be made because the time of exposure is primarily controlled by this portion of the cam. Of course, the. factors ofv the-time of opening and closing the shutter blades cannot be separately controlled because the slope of the cam I1 and the speed of the master member II control the opening movement of the shutter blades and the light spring controls the closing movement. It has been found, however, that the construction shown in the drawing. lends itself to the construction of a quite efficient shutter because the blades are held in their fully-opened position by the cam portionl'l" and because this portion of the ex posure time is a comparatively large percent of the total time that the blades are open from the start. of the opening movement to the completion of the closing movement. I I

Moreover, the construction outlined above is extremely simple so that the shutter may be readily constructed and assembled.

- I am aware that two blade shutters of the same general type have been made and patented before, but in most instances the construction is much more complicated than the construction which *I use primarily because it has been customary to interpose one or more additional levers between the master member and the bladeoperating member. By providing theblade-opcrating member in the formof a pin carried by one blade and engaging the otherand by having the mastermember directly engage this pin, a much simpler and more eflicient structure is provided. In addition, the spring cam arm need not be particularly accurately made and the degree of spring in the material does not have to be accurately maintained because the cam flange 1 strikes the edgefof the master member I I during its driven stroke to open the blades. When, however, the master member is being set, the spring cam member needs only sufiicient resilience to permit the blade driving pin 9 to .pass as indicated above.

",1 claim;

slips oftthe master member releasing it for cam and pin to move the blades to an open position when said master member move toward its rest position, and a shutter trigger including an .arm positioned to engage and move the master member from its rest position until it movement under its spring.

2. A camera shutter comprising, in combination, an apertured support, a pair of shutter blades pivotally mounted thereon on spaced pivots, one blade carrying a pin projecting through aslotin the other blade, a master member pivotally carried by the support and spring held in a rest position, a spring flange carried by the master member including a cam shaped end and having a cut out therein, the spring cam end lying in a position in which'the master member forms a stop preventing flexing except in a direction away from the master member, said mas ter member pivot being so. located relative to the blade that movement on said pivot may engage the cam and pin to move the bladesto an open position when said master member moves toward its rest position, and a shutter trigger including an arm positioned to engage and move the master member from its rest position until it slips off the master member releasing it for movement oted master member adapted to be moved and released by the operating arm, and a'spring cam carried by the master member and positioned to I verse direction, and a spring tending to hold the engage and move the single blade operating pin when said master member moves in one direction moved and released by the operating arm, and

a spring cam carried by the master member and positioned to engage and move the single blade operating pin when said master member moves in one direction and to flex without'moving said pin when the master memberis moved in a reblade operating pin in a position of rest in which the shutter blades close the aperture in the support.

5. A camera shutter, comprising, in combina--- tion, an apertured support, two blades pivotally mounted thereon, a single blade operating pin carried by one blade and operatively engaging the other blade, a shutter trigger; pivotally mounted on the shutter having an operating arm, a pivoted master member adapted .to be moved and released by the operating arm, and a spring cam carried by the master member and positioned to engage and move the single blade operating pin when said master member moves in one direction and to flex without moving said pin when the master member is moved ina reverse direction, and a spring tending to hold the blade operating pin in a position of rest in which the shutter blades close the aperture in the support, the spring cam including a cut out area through which the blade opening pin passes after the master member has opened the blades and positioned to engage and move the single blade operating pin when said master member moves in one directionand to flex without moving said pin when the master member is moved in a reverse direction, and a spring tending to hold the blade operating pin in a position of rest in which the shutter blades close the aperture in the support, the spring cam including a beveled cam surface and a substantially arcuate cam surface ending at a cut out portion whereby movement of the master member may drive the blades open and hold them open in moving in one direction and may cause the spring cam to flex in moving in an opposite direction whereby in setting the master member the cam may spring about the blade operating pin.

7. A camera shutter comprising, in combina tion, an apertured support, a blade pivotally mounted thereon, a single blade operating pin carried by the blade, a spring normally holding the blade over the aperture, a shutter trigger pivotal-1y mounted on the shutter and having an operating arm, a pivoted master member adapted to be moved and released by the operating arm, a spring cam carried by the master member extending in a generally concentric direction about the master member pivot except for. the extreme end 01 the cam which is bent at an angle, said spring cam being positioned to engage and move the single blade operating pin when said master member moves in one direction and to flex without moving the min when the master member moves in a reverse direction, said spring cam including a cut out portion spaced from the end of the spring cam and of a size to permit the free passage of the blade operating pin after said cam has moved said pin whereby said spring may move said blade to its normal position over Y '30 the aperture.

CARL c. FUERsT. 

